On-highway work machines, such as semi-tractor or class-8 trucks, are often equipped with a sleeper cabin disposed behind an operator cab. Heating and cooling systems for these machines often are configured to provide airflow to one of the operator cab and sleeper cabin independent of the other. Accordingly, an operator may control the heating and cooling in the two areas as desired.
One known system for independent control of the heating and cooling to an operator cab provides two separate heating and cooling systems: a first heating and cooling unit dedicated to the sleeper cabin; and a second heating and cooling unit dedicated to the operator cab. However, such a system requires two of every component, increasing the overall cost of the system.
Another known system includes a single heating or cooling system with outlet vents directed into the cab and the sleeper cabin. One example of such a system is disclosed in U.S. Pat. No. 6,196,308 to Halligan. The '308 patent discloses a system of heating and cooling both a sleeper cabin and an operator cab on an on-highway truck. The system is disposed below the operator's seat and includes one outlet vent directed to the sleeper cabin and another outlet vent directed into the operator cab. A first controllable blower pushes air from a common inlet into the operator cab and a second controllable blower pushes air from the common inlet into the sleeper cabin. Independent controls in each of the operator cab and the sleeper cabin control the airflow of the blower blowing air into that cab and cabin. However, maintaining two blowers in a single cooling system can be redundant and, because each component increases the cost of the system, can be more expensive than necessary. Further, having two blowers in the system may increase the likelihood that one of the blowers will experience mechanical or electrical problems over time.
This disclosure is directed to an airflow control system that overcomes one or more of the deficiencies of the prior art.